mirror of
https://gitlab.sectorq.eu/jaydee/omv_backup.git
synced 2025-07-04 00:45:50 +02:00
added v3
This commit is contained in:
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# This file is dual licensed under the terms of the Apache License, Version
|
||||
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
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||||
# for complete details.
|
||||
|
||||
from __future__ import annotations
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||||
|
||||
from cryptography.hazmat.primitives._cipheralgorithm import (
|
||||
BlockCipherAlgorithm,
|
||||
CipherAlgorithm,
|
||||
)
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from cryptography.hazmat.primitives.ciphers.base import (
|
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AEADCipherContext,
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AEADDecryptionContext,
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AEADEncryptionContext,
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||||
Cipher,
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||||
CipherContext,
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||||
)
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__all__ = [
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"AEADCipherContext",
|
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"AEADDecryptionContext",
|
||||
"AEADEncryptionContext",
|
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"BlockCipherAlgorithm",
|
||||
"Cipher",
|
||||
"CipherAlgorithm",
|
||||
"CipherContext",
|
||||
]
|
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# This file is dual licensed under the terms of the Apache License, Version
|
||||
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
|
||||
# for complete details.
|
||||
|
||||
from __future__ import annotations
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||||
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||||
from cryptography.hazmat.bindings._rust import openssl as rust_openssl
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__all__ = [
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"AESCCM",
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"AESGCM",
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"AESGCMSIV",
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||||
"AESOCB3",
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"AESSIV",
|
||||
"ChaCha20Poly1305",
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||||
]
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||||
|
||||
AESGCM = rust_openssl.aead.AESGCM
|
||||
ChaCha20Poly1305 = rust_openssl.aead.ChaCha20Poly1305
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AESCCM = rust_openssl.aead.AESCCM
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AESSIV = rust_openssl.aead.AESSIV
|
||||
AESOCB3 = rust_openssl.aead.AESOCB3
|
||||
AESGCMSIV = rust_openssl.aead.AESGCMSIV
|
@ -0,0 +1,183 @@
|
||||
# This file is dual licensed under the terms of the Apache License, Version
|
||||
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
|
||||
# for complete details.
|
||||
|
||||
from __future__ import annotations
|
||||
|
||||
from cryptography import utils
|
||||
from cryptography.hazmat.decrepit.ciphers.algorithms import (
|
||||
ARC4 as ARC4,
|
||||
)
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from cryptography.hazmat.decrepit.ciphers.algorithms import (
|
||||
CAST5 as CAST5,
|
||||
)
|
||||
from cryptography.hazmat.decrepit.ciphers.algorithms import (
|
||||
IDEA as IDEA,
|
||||
)
|
||||
from cryptography.hazmat.decrepit.ciphers.algorithms import (
|
||||
SEED as SEED,
|
||||
)
|
||||
from cryptography.hazmat.decrepit.ciphers.algorithms import (
|
||||
Blowfish as Blowfish,
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||||
)
|
||||
from cryptography.hazmat.decrepit.ciphers.algorithms import (
|
||||
TripleDES as TripleDES,
|
||||
)
|
||||
from cryptography.hazmat.primitives._cipheralgorithm import _verify_key_size
|
||||
from cryptography.hazmat.primitives.ciphers import (
|
||||
BlockCipherAlgorithm,
|
||||
CipherAlgorithm,
|
||||
)
|
||||
|
||||
|
||||
class AES(BlockCipherAlgorithm):
|
||||
name = "AES"
|
||||
block_size = 128
|
||||
# 512 added to support AES-256-XTS, which uses 512-bit keys
|
||||
key_sizes = frozenset([128, 192, 256, 512])
|
||||
|
||||
def __init__(self, key: bytes):
|
||||
self.key = _verify_key_size(self, key)
|
||||
|
||||
@property
|
||||
def key_size(self) -> int:
|
||||
return len(self.key) * 8
|
||||
|
||||
|
||||
class AES128(BlockCipherAlgorithm):
|
||||
name = "AES"
|
||||
block_size = 128
|
||||
key_sizes = frozenset([128])
|
||||
key_size = 128
|
||||
|
||||
def __init__(self, key: bytes):
|
||||
self.key = _verify_key_size(self, key)
|
||||
|
||||
|
||||
class AES256(BlockCipherAlgorithm):
|
||||
name = "AES"
|
||||
block_size = 128
|
||||
key_sizes = frozenset([256])
|
||||
key_size = 256
|
||||
|
||||
def __init__(self, key: bytes):
|
||||
self.key = _verify_key_size(self, key)
|
||||
|
||||
|
||||
class Camellia(BlockCipherAlgorithm):
|
||||
name = "camellia"
|
||||
block_size = 128
|
||||
key_sizes = frozenset([128, 192, 256])
|
||||
|
||||
def __init__(self, key: bytes):
|
||||
self.key = _verify_key_size(self, key)
|
||||
|
||||
@property
|
||||
def key_size(self) -> int:
|
||||
return len(self.key) * 8
|
||||
|
||||
|
||||
utils.deprecated(
|
||||
ARC4,
|
||||
__name__,
|
||||
"ARC4 has been moved to "
|
||||
"cryptography.hazmat.decrepit.ciphers.algorithms.ARC4 and "
|
||||
"will be removed from "
|
||||
"cryptography.hazmat.primitives.ciphers.algorithms in 48.0.0.",
|
||||
utils.DeprecatedIn43,
|
||||
name="ARC4",
|
||||
)
|
||||
|
||||
|
||||
utils.deprecated(
|
||||
TripleDES,
|
||||
__name__,
|
||||
"TripleDES has been moved to "
|
||||
"cryptography.hazmat.decrepit.ciphers.algorithms.TripleDES and "
|
||||
"will be removed from "
|
||||
"cryptography.hazmat.primitives.ciphers.algorithms in 48.0.0.",
|
||||
utils.DeprecatedIn43,
|
||||
name="TripleDES",
|
||||
)
|
||||
|
||||
utils.deprecated(
|
||||
Blowfish,
|
||||
__name__,
|
||||
"Blowfish has been moved to "
|
||||
"cryptography.hazmat.decrepit.ciphers.algorithms.Blowfish and "
|
||||
"will be removed from "
|
||||
"cryptography.hazmat.primitives.ciphers.algorithms in 45.0.0.",
|
||||
utils.DeprecatedIn37,
|
||||
name="Blowfish",
|
||||
)
|
||||
|
||||
|
||||
utils.deprecated(
|
||||
CAST5,
|
||||
__name__,
|
||||
"CAST5 has been moved to "
|
||||
"cryptography.hazmat.decrepit.ciphers.algorithms.CAST5 and "
|
||||
"will be removed from "
|
||||
"cryptography.hazmat.primitives.ciphers.algorithms in 45.0.0.",
|
||||
utils.DeprecatedIn37,
|
||||
name="CAST5",
|
||||
)
|
||||
|
||||
|
||||
utils.deprecated(
|
||||
IDEA,
|
||||
__name__,
|
||||
"IDEA has been moved to "
|
||||
"cryptography.hazmat.decrepit.ciphers.algorithms.IDEA and "
|
||||
"will be removed from "
|
||||
"cryptography.hazmat.primitives.ciphers.algorithms in 45.0.0.",
|
||||
utils.DeprecatedIn37,
|
||||
name="IDEA",
|
||||
)
|
||||
|
||||
|
||||
utils.deprecated(
|
||||
SEED,
|
||||
__name__,
|
||||
"SEED has been moved to "
|
||||
"cryptography.hazmat.decrepit.ciphers.algorithms.SEED and "
|
||||
"will be removed from "
|
||||
"cryptography.hazmat.primitives.ciphers.algorithms in 45.0.0.",
|
||||
utils.DeprecatedIn37,
|
||||
name="SEED",
|
||||
)
|
||||
|
||||
|
||||
class ChaCha20(CipherAlgorithm):
|
||||
name = "ChaCha20"
|
||||
key_sizes = frozenset([256])
|
||||
|
||||
def __init__(self, key: bytes, nonce: bytes):
|
||||
self.key = _verify_key_size(self, key)
|
||||
utils._check_byteslike("nonce", nonce)
|
||||
|
||||
if len(nonce) != 16:
|
||||
raise ValueError("nonce must be 128-bits (16 bytes)")
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||||
|
||||
self._nonce = nonce
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||||
|
||||
@property
|
||||
def nonce(self) -> bytes:
|
||||
return self._nonce
|
||||
|
||||
@property
|
||||
def key_size(self) -> int:
|
||||
return len(self.key) * 8
|
||||
|
||||
|
||||
class SM4(BlockCipherAlgorithm):
|
||||
name = "SM4"
|
||||
block_size = 128
|
||||
key_sizes = frozenset([128])
|
||||
|
||||
def __init__(self, key: bytes):
|
||||
self.key = _verify_key_size(self, key)
|
||||
|
||||
@property
|
||||
def key_size(self) -> int:
|
||||
return len(self.key) * 8
|
@ -0,0 +1,145 @@
|
||||
# This file is dual licensed under the terms of the Apache License, Version
|
||||
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
|
||||
# for complete details.
|
||||
|
||||
from __future__ import annotations
|
||||
|
||||
import abc
|
||||
import typing
|
||||
|
||||
from cryptography.hazmat.bindings._rust import openssl as rust_openssl
|
||||
from cryptography.hazmat.primitives._cipheralgorithm import CipherAlgorithm
|
||||
from cryptography.hazmat.primitives.ciphers import modes
|
||||
|
||||
|
||||
class CipherContext(metaclass=abc.ABCMeta):
|
||||
@abc.abstractmethod
|
||||
def update(self, data: bytes) -> bytes:
|
||||
"""
|
||||
Processes the provided bytes through the cipher and returns the results
|
||||
as bytes.
|
||||
"""
|
||||
|
||||
@abc.abstractmethod
|
||||
def update_into(self, data: bytes, buf: bytes) -> int:
|
||||
"""
|
||||
Processes the provided bytes and writes the resulting data into the
|
||||
provided buffer. Returns the number of bytes written.
|
||||
"""
|
||||
|
||||
@abc.abstractmethod
|
||||
def finalize(self) -> bytes:
|
||||
"""
|
||||
Returns the results of processing the final block as bytes.
|
||||
"""
|
||||
|
||||
@abc.abstractmethod
|
||||
def reset_nonce(self, nonce: bytes) -> None:
|
||||
"""
|
||||
Resets the nonce for the cipher context to the provided value.
|
||||
Raises an exception if it does not support reset or if the
|
||||
provided nonce does not have a valid length.
|
||||
"""
|
||||
|
||||
|
||||
class AEADCipherContext(CipherContext, metaclass=abc.ABCMeta):
|
||||
@abc.abstractmethod
|
||||
def authenticate_additional_data(self, data: bytes) -> None:
|
||||
"""
|
||||
Authenticates the provided bytes.
|
||||
"""
|
||||
|
||||
|
||||
class AEADDecryptionContext(AEADCipherContext, metaclass=abc.ABCMeta):
|
||||
@abc.abstractmethod
|
||||
def finalize_with_tag(self, tag: bytes) -> bytes:
|
||||
"""
|
||||
Returns the results of processing the final block as bytes and allows
|
||||
delayed passing of the authentication tag.
|
||||
"""
|
||||
|
||||
|
||||
class AEADEncryptionContext(AEADCipherContext, metaclass=abc.ABCMeta):
|
||||
@property
|
||||
@abc.abstractmethod
|
||||
def tag(self) -> bytes:
|
||||
"""
|
||||
Returns tag bytes. This is only available after encryption is
|
||||
finalized.
|
||||
"""
|
||||
|
||||
|
||||
Mode = typing.TypeVar(
|
||||
"Mode", bound=typing.Optional[modes.Mode], covariant=True
|
||||
)
|
||||
|
||||
|
||||
class Cipher(typing.Generic[Mode]):
|
||||
def __init__(
|
||||
self,
|
||||
algorithm: CipherAlgorithm,
|
||||
mode: Mode,
|
||||
backend: typing.Any = None,
|
||||
) -> None:
|
||||
if not isinstance(algorithm, CipherAlgorithm):
|
||||
raise TypeError("Expected interface of CipherAlgorithm.")
|
||||
|
||||
if mode is not None:
|
||||
# mypy needs this assert to narrow the type from our generic
|
||||
# type. Maybe it won't some time in the future.
|
||||
assert isinstance(mode, modes.Mode)
|
||||
mode.validate_for_algorithm(algorithm)
|
||||
|
||||
self.algorithm = algorithm
|
||||
self.mode = mode
|
||||
|
||||
@typing.overload
|
||||
def encryptor(
|
||||
self: Cipher[modes.ModeWithAuthenticationTag],
|
||||
) -> AEADEncryptionContext: ...
|
||||
|
||||
@typing.overload
|
||||
def encryptor(
|
||||
self: _CIPHER_TYPE,
|
||||
) -> CipherContext: ...
|
||||
|
||||
def encryptor(self):
|
||||
if isinstance(self.mode, modes.ModeWithAuthenticationTag):
|
||||
if self.mode.tag is not None:
|
||||
raise ValueError(
|
||||
"Authentication tag must be None when encrypting."
|
||||
)
|
||||
|
||||
return rust_openssl.ciphers.create_encryption_ctx(
|
||||
self.algorithm, self.mode
|
||||
)
|
||||
|
||||
@typing.overload
|
||||
def decryptor(
|
||||
self: Cipher[modes.ModeWithAuthenticationTag],
|
||||
) -> AEADDecryptionContext: ...
|
||||
|
||||
@typing.overload
|
||||
def decryptor(
|
||||
self: _CIPHER_TYPE,
|
||||
) -> CipherContext: ...
|
||||
|
||||
def decryptor(self):
|
||||
return rust_openssl.ciphers.create_decryption_ctx(
|
||||
self.algorithm, self.mode
|
||||
)
|
||||
|
||||
|
||||
_CIPHER_TYPE = Cipher[
|
||||
typing.Union[
|
||||
modes.ModeWithNonce,
|
||||
modes.ModeWithTweak,
|
||||
None,
|
||||
modes.ECB,
|
||||
modes.ModeWithInitializationVector,
|
||||
]
|
||||
]
|
||||
|
||||
CipherContext.register(rust_openssl.ciphers.CipherContext)
|
||||
AEADEncryptionContext.register(rust_openssl.ciphers.AEADEncryptionContext)
|
||||
AEADDecryptionContext.register(rust_openssl.ciphers.AEADDecryptionContext)
|
@ -0,0 +1,268 @@
|
||||
# This file is dual licensed under the terms of the Apache License, Version
|
||||
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
|
||||
# for complete details.
|
||||
|
||||
from __future__ import annotations
|
||||
|
||||
import abc
|
||||
|
||||
from cryptography import utils
|
||||
from cryptography.exceptions import UnsupportedAlgorithm, _Reasons
|
||||
from cryptography.hazmat.primitives._cipheralgorithm import (
|
||||
BlockCipherAlgorithm,
|
||||
CipherAlgorithm,
|
||||
)
|
||||
from cryptography.hazmat.primitives.ciphers import algorithms
|
||||
|
||||
|
||||
class Mode(metaclass=abc.ABCMeta):
|
||||
@property
|
||||
@abc.abstractmethod
|
||||
def name(self) -> str:
|
||||
"""
|
||||
A string naming this mode (e.g. "ECB", "CBC").
|
||||
"""
|
||||
|
||||
@abc.abstractmethod
|
||||
def validate_for_algorithm(self, algorithm: CipherAlgorithm) -> None:
|
||||
"""
|
||||
Checks that all the necessary invariants of this (mode, algorithm)
|
||||
combination are met.
|
||||
"""
|
||||
|
||||
|
||||
class ModeWithInitializationVector(Mode, metaclass=abc.ABCMeta):
|
||||
@property
|
||||
@abc.abstractmethod
|
||||
def initialization_vector(self) -> bytes:
|
||||
"""
|
||||
The value of the initialization vector for this mode as bytes.
|
||||
"""
|
||||
|
||||
|
||||
class ModeWithTweak(Mode, metaclass=abc.ABCMeta):
|
||||
@property
|
||||
@abc.abstractmethod
|
||||
def tweak(self) -> bytes:
|
||||
"""
|
||||
The value of the tweak for this mode as bytes.
|
||||
"""
|
||||
|
||||
|
||||
class ModeWithNonce(Mode, metaclass=abc.ABCMeta):
|
||||
@property
|
||||
@abc.abstractmethod
|
||||
def nonce(self) -> bytes:
|
||||
"""
|
||||
The value of the nonce for this mode as bytes.
|
||||
"""
|
||||
|
||||
|
||||
class ModeWithAuthenticationTag(Mode, metaclass=abc.ABCMeta):
|
||||
@property
|
||||
@abc.abstractmethod
|
||||
def tag(self) -> bytes | None:
|
||||
"""
|
||||
The value of the tag supplied to the constructor of this mode.
|
||||
"""
|
||||
|
||||
|
||||
def _check_aes_key_length(self: Mode, algorithm: CipherAlgorithm) -> None:
|
||||
if algorithm.key_size > 256 and algorithm.name == "AES":
|
||||
raise ValueError(
|
||||
"Only 128, 192, and 256 bit keys are allowed for this AES mode"
|
||||
)
|
||||
|
||||
|
||||
def _check_iv_length(
|
||||
self: ModeWithInitializationVector, algorithm: BlockCipherAlgorithm
|
||||
) -> None:
|
||||
iv_len = len(self.initialization_vector)
|
||||
if iv_len * 8 != algorithm.block_size:
|
||||
raise ValueError(f"Invalid IV size ({iv_len}) for {self.name}.")
|
||||
|
||||
|
||||
def _check_nonce_length(
|
||||
nonce: bytes, name: str, algorithm: CipherAlgorithm
|
||||
) -> None:
|
||||
if not isinstance(algorithm, BlockCipherAlgorithm):
|
||||
raise UnsupportedAlgorithm(
|
||||
f"{name} requires a block cipher algorithm",
|
||||
_Reasons.UNSUPPORTED_CIPHER,
|
||||
)
|
||||
if len(nonce) * 8 != algorithm.block_size:
|
||||
raise ValueError(f"Invalid nonce size ({len(nonce)}) for {name}.")
|
||||
|
||||
|
||||
def _check_iv_and_key_length(
|
||||
self: ModeWithInitializationVector, algorithm: CipherAlgorithm
|
||||
) -> None:
|
||||
if not isinstance(algorithm, BlockCipherAlgorithm):
|
||||
raise UnsupportedAlgorithm(
|
||||
f"{self} requires a block cipher algorithm",
|
||||
_Reasons.UNSUPPORTED_CIPHER,
|
||||
)
|
||||
_check_aes_key_length(self, algorithm)
|
||||
_check_iv_length(self, algorithm)
|
||||
|
||||
|
||||
class CBC(ModeWithInitializationVector):
|
||||
name = "CBC"
|
||||
|
||||
def __init__(self, initialization_vector: bytes):
|
||||
utils._check_byteslike("initialization_vector", initialization_vector)
|
||||
self._initialization_vector = initialization_vector
|
||||
|
||||
@property
|
||||
def initialization_vector(self) -> bytes:
|
||||
return self._initialization_vector
|
||||
|
||||
validate_for_algorithm = _check_iv_and_key_length
|
||||
|
||||
|
||||
class XTS(ModeWithTweak):
|
||||
name = "XTS"
|
||||
|
||||
def __init__(self, tweak: bytes):
|
||||
utils._check_byteslike("tweak", tweak)
|
||||
|
||||
if len(tweak) != 16:
|
||||
raise ValueError("tweak must be 128-bits (16 bytes)")
|
||||
|
||||
self._tweak = tweak
|
||||
|
||||
@property
|
||||
def tweak(self) -> bytes:
|
||||
return self._tweak
|
||||
|
||||
def validate_for_algorithm(self, algorithm: CipherAlgorithm) -> None:
|
||||
if isinstance(algorithm, (algorithms.AES128, algorithms.AES256)):
|
||||
raise TypeError(
|
||||
"The AES128 and AES256 classes do not support XTS, please use "
|
||||
"the standard AES class instead."
|
||||
)
|
||||
|
||||
if algorithm.key_size not in (256, 512):
|
||||
raise ValueError(
|
||||
"The XTS specification requires a 256-bit key for AES-128-XTS"
|
||||
" and 512-bit key for AES-256-XTS"
|
||||
)
|
||||
|
||||
|
||||
class ECB(Mode):
|
||||
name = "ECB"
|
||||
|
||||
validate_for_algorithm = _check_aes_key_length
|
||||
|
||||
|
||||
class OFB(ModeWithInitializationVector):
|
||||
name = "OFB"
|
||||
|
||||
def __init__(self, initialization_vector: bytes):
|
||||
utils._check_byteslike("initialization_vector", initialization_vector)
|
||||
self._initialization_vector = initialization_vector
|
||||
|
||||
@property
|
||||
def initialization_vector(self) -> bytes:
|
||||
return self._initialization_vector
|
||||
|
||||
validate_for_algorithm = _check_iv_and_key_length
|
||||
|
||||
|
||||
class CFB(ModeWithInitializationVector):
|
||||
name = "CFB"
|
||||
|
||||
def __init__(self, initialization_vector: bytes):
|
||||
utils._check_byteslike("initialization_vector", initialization_vector)
|
||||
self._initialization_vector = initialization_vector
|
||||
|
||||
@property
|
||||
def initialization_vector(self) -> bytes:
|
||||
return self._initialization_vector
|
||||
|
||||
validate_for_algorithm = _check_iv_and_key_length
|
||||
|
||||
|
||||
class CFB8(ModeWithInitializationVector):
|
||||
name = "CFB8"
|
||||
|
||||
def __init__(self, initialization_vector: bytes):
|
||||
utils._check_byteslike("initialization_vector", initialization_vector)
|
||||
self._initialization_vector = initialization_vector
|
||||
|
||||
@property
|
||||
def initialization_vector(self) -> bytes:
|
||||
return self._initialization_vector
|
||||
|
||||
validate_for_algorithm = _check_iv_and_key_length
|
||||
|
||||
|
||||
class CTR(ModeWithNonce):
|
||||
name = "CTR"
|
||||
|
||||
def __init__(self, nonce: bytes):
|
||||
utils._check_byteslike("nonce", nonce)
|
||||
self._nonce = nonce
|
||||
|
||||
@property
|
||||
def nonce(self) -> bytes:
|
||||
return self._nonce
|
||||
|
||||
def validate_for_algorithm(self, algorithm: CipherAlgorithm) -> None:
|
||||
_check_aes_key_length(self, algorithm)
|
||||
_check_nonce_length(self.nonce, self.name, algorithm)
|
||||
|
||||
|
||||
class GCM(ModeWithInitializationVector, ModeWithAuthenticationTag):
|
||||
name = "GCM"
|
||||
_MAX_ENCRYPTED_BYTES = (2**39 - 256) // 8
|
||||
_MAX_AAD_BYTES = (2**64) // 8
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
initialization_vector: bytes,
|
||||
tag: bytes | None = None,
|
||||
min_tag_length: int = 16,
|
||||
):
|
||||
# OpenSSL 3.0.0 constrains GCM IVs to [64, 1024] bits inclusive
|
||||
# This is a sane limit anyway so we'll enforce it here.
|
||||
utils._check_byteslike("initialization_vector", initialization_vector)
|
||||
if len(initialization_vector) < 8 or len(initialization_vector) > 128:
|
||||
raise ValueError(
|
||||
"initialization_vector must be between 8 and 128 bytes (64 "
|
||||
"and 1024 bits)."
|
||||
)
|
||||
self._initialization_vector = initialization_vector
|
||||
if tag is not None:
|
||||
utils._check_bytes("tag", tag)
|
||||
if min_tag_length < 4:
|
||||
raise ValueError("min_tag_length must be >= 4")
|
||||
if len(tag) < min_tag_length:
|
||||
raise ValueError(
|
||||
f"Authentication tag must be {min_tag_length} bytes or "
|
||||
"longer."
|
||||
)
|
||||
self._tag = tag
|
||||
self._min_tag_length = min_tag_length
|
||||
|
||||
@property
|
||||
def tag(self) -> bytes | None:
|
||||
return self._tag
|
||||
|
||||
@property
|
||||
def initialization_vector(self) -> bytes:
|
||||
return self._initialization_vector
|
||||
|
||||
def validate_for_algorithm(self, algorithm: CipherAlgorithm) -> None:
|
||||
_check_aes_key_length(self, algorithm)
|
||||
if not isinstance(algorithm, BlockCipherAlgorithm):
|
||||
raise UnsupportedAlgorithm(
|
||||
"GCM requires a block cipher algorithm",
|
||||
_Reasons.UNSUPPORTED_CIPHER,
|
||||
)
|
||||
block_size_bytes = algorithm.block_size // 8
|
||||
if self._tag is not None and len(self._tag) > block_size_bytes:
|
||||
raise ValueError(
|
||||
f"Authentication tag cannot be more than {block_size_bytes} "
|
||||
"bytes."
|
||||
)
|
Reference in New Issue
Block a user